Quad ring patch antenna design for VHF/UHF application

Abstract

Current trend of greater mobility of wireless communication devices has stimulated designs of portability to be at the forefront of manufacturer's interest. In fact, micro strip patch antenna has gain greater popularity because of their many advantages such as, light weight, low fabrication cost, polarization diversity and ease of integration with microwave integrated circuits. This paper covers the Quad ring patch antenna design for UHF (Ultra high frequency) and VHF (very high frequency) application. The Quad ring patch antenna will have a gain of 10 dB and above. Four ring patch antennas are placed in the array form and are joined by a Wilkinson power divider at one point in order to equally divide the power among the circular ring and make the power lossless. A Balun was incorporated at the feed point of the antenna so as to match the impedance of the coaxial cable with the impedance of the Quad ring patch antenna in order to ensure maximum power transfer. This uniquely designed array structure was tested on television application and the result shows that such portable array of reduced size was well receptive towards such frequency range. This portable antenna which was kept at close proximity with the television was able to produce relatively good quality signal over three channels under a static position. In fact, these results can be very useful while designing micro-strip patch antenna of different structure and array.